Films or sheets of polymeric barrier materials are formed into a finished package or “film package” such as a pouch by various techniques, for instance, by forming heat or adhesive seals about the periphery of the shape to be formed into a pouch. For example, if a square pouch is desired, a rectangular film twice the desired length of the pouch is folded, the two parallel sides of the periphery (perpendicular to the fold) heat or adhesive sealed, or, the two parallel sides and the fold are heat or adhesive sealed, the food or other material to be packaged inserted therein, and then the remaining open side of the periphery is heat or adhesive sealed. Another method for making a pouch is by sealing on three sides face-to-face films, filling the thus formed open pouch with food or whatever material is to be packaged therein, and then sealing the fourth side. For background on pouches or bags and their production, reference is made to U.S. Pat. Nos. 4,190,477, 4,311,742, 4,360,550, 4,424,256, 4,557,377, and 5,630,308, each of which is incorporated herein by reference.
The problem encountered by the end user of the food or material within the pouch is how to open the pouch. The pouches are usually formed from tough or strong polymeric barrier materials so the pouches do not open easily. One method for opening such pouches is to manually rip at the pouch, which usually results in its contents spilling all about. Another method is simply cutting open the pouch with a scissor, knife or other sharp object. It is desirable to be able to neatly open a pouch without the need to use a cutting instrument. Furthermore, the problem of how to open a pouch is really two-fold. The first problem is how to initiate the opening. The second problem is providing control of the opening across the entire pouch.
A variety of solutions have been proposed in the art and are summarized in U.S. Pat. No. 5,630,308, cited above. In fact, the '308 patent solves this problem by laser scoring the polymeric laminate structure so as to enable the pouch to be easily opened along one of the laser-created score lines. Of course, laser scoring adds another manufacturing step to the process, thus increasing cost of the ultimate pouch.
The present disclosure proposes to create inherent tearability during the laminate production process to enable facile hand tearing of the laminate structure, while reducing costs by not adding extra steps to the manufacturing process. The need for expensive lasers is eliminated also.